Narrowband networks include a number of infrastructure components for facilitating communications between communication devices. An example of such a narrowband network is a network used by a Project 25 (P25)-compatible two-way Push-To-Talk voice communication system that includes wireless and wired voice and data communication devices. The voice and data communication devices may be, for example, portable narrowband two-way radios, mobile radios, dispatch consoles, or other similar voice and/or data communication entities that communicate with one another via wired and/or wireless networks. A narrowband system may be shared by multiple groups of users (each group of users is referred to herein as an agency, which may be associated with, for example, a fire department, police department, retail store, etc.). Each agency typically uses a fraction of the radio frequency (RF) resources (for example, data channels) available on the system to meet the agency's communication needs.
When data channels are assigned to one or more agencies, the data channel's bandwidth could be partitioned among the agencies, using well-known techniques. In some implementations, when one or more data channels are shared by multiple agencies, each agency is assigned a percentage of the data channel's bandwidth. If a fixed percentage of the available data channel's bandwidth is assigned to a specific agency, when the agency is not using all of its assigned bandwidth at any given time, this bandwidth goes to waste and is not utilized. When data channels are shared by multiple agencies, some means is necessary to guarantee minimum data bandwidth to agencies when the total data bandwidth is fully utilized. In addition, there needs to be an avenue for allowing those agencies that are not guaranteed data bandwidth use of unused portions of the guaranteed bandwidth during slow periods.
Accordingly, there is a need for an improved method and apparatus for sharing a data channel bandwidth between multiple agencies and controlling each agency's access to the data channel bandwidth.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.